Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
O'Dea Louis
   2. Issuer Name and Ticker or Trading Symbol
Radius Health, Inc. [NONE] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Sr VP, Chief Medical Officer
(Last)
(First)
(Middle)
C/O RADIUS HEALTH, INC., 201 BROADWAY, 6TH FLOOR		 3. Date of Earliest Transaction (Month/Day/Year)
05/17/2011
(Street)

CAMBRIDGE, MA 02139		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 05/17/2011   A   29,207 A (1) 29,207 D  

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Option (Right to Buy) $ 1.5 05/17/2011   A   22,642     (2) 02/15/2016 Common Stock 22,642 (3) 22,642 D  
Stock Option (Right to Buy) $ 0.9 05/17/2011   A   41,547     (4) 07/12/2017 Common Stock 41,547 (5) 41,547 D  
Stock Option (Right to Buy) $ 1.2 05/17/2011   A   70,935     (6) 05/08/2018 Common Stock 70,935 (7) 70,935 D  
Stock Option (Right to Buy) $ 1.2 05/17/2011   A   30,231     (8) 12/03/2018 Common Stock 30,231 (9) 30,231 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
O'Dea Louis
C/O RADIUS HEALTH, INC.
201 BROADWAY, 6TH FLOOR
CAMBRIDGE, MA 02139		       Sr VP, Chief Medical Officer  

Signatures

 /s/ B. Nicholas Harvey, attorney-in-fact   05/19/2011
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Received in exchange for 29,207 shares of common stock of Radius Health, Inc. in connection with the merger of RHI Merger Corp., a wholly-owned subsidiary of the Registrant (f/k/a MPM Acquisition Corp.), with and into Radius Health, Inc. ("Target") pursuant to which Target survived and became a wholly-owned subsidiary of Registrant (the "Surviving Corporation"). Following such merger, the Surviving Corporation merged with and into its parent corporation, the Registrant, and subsequently changed its name to "Radius Health, Inc." (the "Merger").
(2) 25% of the options vested on February 15, 2007. 25% of the options vested in twelve equal quarterly installments with the first quarterly installment vested on May 15, 2007, and the additional quarterly installments vested on the first day of each calendar quarter thereafter, 50% of the options vested on completion of certain milestones.
(3) Received in exchange for employee stock options to acquire 22,642 shares of Radius common stock for $0.10 per share in connection with the Merger.
(4) The options vest in sixteen equal quarterly installments with the first quarterly installment vesting on July 1, 2007, and the additional quarterly installments vesting on the first day of each calendar quarter thereafter.
(5) Received in exchange for employee stock options to acquire 41,547 shares of Radius common stock for $0.06 per share in connection with the Merger.
(6) 17,733 of the options vested on May 8, 2008, and the remaining options vest in twelve equal quarterly installments with the first quarterly installment vesting on October 1, 2008, and the additional quarterly installments vesting on the first day of each calendar quarter thereafter.
(7) Received in exchange for employee stock options to acquire 70,935 shares of Radius common stock for $0.08 per share in connection with the Merger.
(8) The options vest in sixteen equal quarterly installments with the first quarterly installment vesting on January 1, 2009, and the additional quarterly installments vesting on the first day of each calendar quarter thereafter.
(9) Received in exchange for employee stock options to acquire 30,321 shares of Radius common stock for $0.08 per share in connection with the Merger.

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